1. Field of the Invention:
This invention in general relates to transducers, and particularly to high frequency sonar transducers.
2. Description of the Prior Art:
In general, high frequency sonar beam patterns are determined by the shape of the active surface of the transducer elements used to project or receive the acoustic energy. The most common surfaces are rectangular, circular, or annular.
In order to obtain a specific beam pattern, with these standard shaped elements, complex arrays must be designed, use must be made of amplitude and phase shading, or reflectors must be employed. These techniques are increasingly difficult at higher frequencies and become prohibitively costly.